煤岩轴向应力恒定卸围压条件下力学参数的研究

分析了煤岩轴向应力恒定卸围压破坏时极限强度、峰值应变和破坏方式等力学参数，运用卸载破坏围压差的概念，反应不同初始卸载围压煤岩破坏的难易程度。通过对不同初始卸荷速率煤岩试件变形破坏力学参数的对比，研究开挖卸荷速率对地下工程的影响。

Research on Mechanical Parameters Under the Condition of Unloading Confining Pressure in Constant Axial Stress of Coal Rock

As a coal rock was destroyed under unloading confining pressure in the constant axial stress,the mechanical parameters such as limit strength,peak value strain and destroying mode were analyzed.A concept of unloading destroying confining pressure difference was used to show destroying degree of different initial unloading confining pressures of the coal rock.Comparison of deformation and destruction mechanical parameters acquired in the tests of different initial unloading velocities of the coal rock was carried out and the influence of excavating unloading velocity on underground engineering was studied.